As a hybrid automobile or an electric automobile is miniaturized, there is a request for miniaturization of a power conversion device used in these vehicles. Therefore, the power conversion device can be miniaturized by reducing dead spaces by miniaturizing components such as a power semiconductor module used in the power conversion device, and by closely disposing the components (for example, a circuit board and the power semiconductor module are closely disposed).
However, in a case where the components are miniaturized and closely disposed, particularly the power-supplied members are necessarily prevented from an erroneous operation of the power conversion device and a risk of an electric shock, and necessarily formed and disposed in consideration of an influence of an electromagnetic noise and an insulating distance. PTL 1 discloses a structure in which a layout distance between a circuit board and the power semiconductor module is increased in order to secure the insulating distance.
However, assuming the mounting on a vehicle, there is a need to achieve miniaturization and space saving by reducing the height of the back surface of a housing for example.